drupal/modules/toolbar/toolbar.module

<?php
// $Id$

/**
 * @file
 * Administration toolbar for quick access to top level administration items.
 */

/**
 * Implementation of hook_permission().
 */
function toolbar_permission() {
  return array(
    'access toolbar' => array(
      'title' => t('Access administration toolbar'),
      'description' => t('Access the persistent administration toolbar displayed on all pages.'),
    ),
  );
}

/**
 * Implement hook_theme().
 */
function toolbar_theme($existing, $type, $theme, $path) {
  $items['toolbar'] = array(
    'arguments' => array('toolbar' => array()),
    'template' => 'toolbar',
    'path' => drupal_get_path('module', 'toolbar'),
  );
  return $items;
}

/**
 * Implement hook_page_build().
 * 
 * Add admin toolbar to the page_top region automatically.
 */
function toolbar_page_build(&$page) {
  if (user_access('access toolbar')) {
    $page['page_top']['toolbar'] = toolbar_build();
  }
}

/**
 * Implement hook_preprocess_page().
 *
 * Add some page classes, so global page theming can adjust to the toolbar.
 */
function toolbar_preprocess_page(&$vars) {
  if (user_access('access toolbar')) {
    $vars['classes_array'][] = 'toolbar toolbar-shortcuts';
  }
}

/**
 * Build the admin menu as a structured array ready for drupal_render().
 */
function toolbar_build() {
  global $user;

  $module_path = drupal_get_path('module', 'toolbar');
  $build = array(
    '#theme' => 'toolbar',
    '#attached'=> array(
      'js' => array(
        $module_path . '/toolbar.js',
        array('data' => 'misc/jquery.cookie.js', 'weight' => JS_LIBRARY + 2),
      ),
      'css' => array(
        $module_path . '/toolbar.css',
      ),
    ),
  );

  // Retrieve the admin menu from the database.
  $links = toolbar_menu_navigation_links(toolbar_get_menu_tree());
  $build['toolbar_menu'] = array(
    '#theme' => 'links',
    '#links' => $links,
    '#attributes' => array('id' => 'toolbar-menu'),
  );

  // Add logout & user account links
  $build['toolbar_user'] = array(
    '#theme' => 'links',
    '#links' => array(
      'account' => array(
        'title' => t('Hello <strong>@username</strong>', array('@username' => $user->name)),
        'href' => 'user',
        'html' => TRUE,
      ),
      'logout' => array(
        'title' => t('Logout'),
        'href' => 'user/logout',
      ),
    ),
    '#attributes' => array('id' => 'toolbar-user'),
  );

  // Add convenience shortcut links.
  $shortcuts = menu_tree_all_data('admin_shortcuts');
  $shortcuts = toolbar_menu_navigation_links($shortcuts);
  $build['toolbar_shortcuts'] = array(
    '#theme' => 'links',
    '#links' => $shortcuts,
    '#attributes' => array('id' => 'toolbar-shortcuts'),
  );

  return $build;
}

/**
 * Get only the top level items below the 'admin' path.
 */
function toolbar_get_menu_tree() {
  $tree = array();
  $admin_link = db_query("SELECT * FROM {menu_links} WHERE menu_name = 'management' AND module = 'system' AND link_path = 'admin'")->fetchAssoc();
  if ($admin_link) {
    $tree = menu_tree_all_data('management', $admin_link);
    // The tree will be a sub-tree with the admin link as a single root item.
    $admin_link = array_pop($tree);
    $tree = $admin_link['below'] ? $admin_link['below'] : array();
    foreach ($tree as $key => $item) {
      // Get rid of subitems to have a leaner data structure.
      unset($tree[$key]['below']);
    }
  }
  return $tree;
}

/**
 * Generate a links array from a menu tree array.
 *
 * Based on menu_navigation_links(). Adds in path based IDs, icon placeholders
 * and overlay classes for the links.
 */
function toolbar_menu_navigation_links($tree) {
  $links = array();
  foreach ($tree as $item) {
    if (!$item['link']['hidden'] && $item['link']['access']) {
      $class = '';
      // Make sure we have a path specific ID in place, so we can attach icons
      // and behaviors to the items.
      $id = str_replace(array('/', '<', '>'), array('-', '', ''), $item['link']['href']);

      $link = $item['link']['localized_options'];
      $link['href'] = $item['link']['href'];
      // Add icon placeholder.
      $link['title'] = '<span class="icon"></span>' . $item['link']['title'];
      // Add admin link ID and to-overlay class for the overlay.
      $link['attributes'] = array('id' => 'toolbar-link-' . $id, 'class' => array('to-overlay'));
      $link['html'] = TRUE;

      $class = ' path-' . $id;
      if (toolbar_in_active_trail($item['link']['href'])) {
        $class .= ' active-trail';
      }
      $links['menu-' . $item['link']['mlid'] . $class] = $link;
    }
  }
  return $links;
}

/**
 * Checks whether an item is in the active trail.
 *
 * Useful when using a menu generated by menu_tree_all_data() which does 
 * not set the 'in_active_trail' flag on items.
 *
 * @todo
 *   Look at migrating to a menu system level function.
 */
function toolbar_in_active_trail($path) {
  $active_paths = &drupal_static(__FUNCTION__);

  // Gather active paths.
  if (!isset($active_paths)) {
    $active_paths = array();
    $trail = menu_get_active_trail();
    foreach ($trail as $item) {
      if (!empty($item['href'])) {
        $active_paths[] = $item['href'];
      }
    }
  }
  return in_array($path, $active_paths);
}